Little is known about the long term hydrologic processes supporting peatlands in the Rocky Mountains. We initiated this study of fen hydrologic processes in 2000, and have continued to collect data for 10 years. We are analyzing a suite of 5 fens, located at 11,000-11,400 feet elevation in the San Juan Mountains of SW Colorado within the boundaries of the Telluride Ski Area. Each fen is instrumented with nests of monitoring wells and piezometers, one to many automated ground water level recorders, temperature sensors, and vegetation plots. We have also measured summer precipitation and watershed snowpack, as well as seasonal carbon fluxes. This site is being used to model the long-term importance of summer rain and winter snowpack in supporting ground water levels and peat formation processes.